“mass bleaching” threatens marine wonder

  • Post last modified:March 8, 2024
  • Reading time:7 mins read


Friday 8 March brought another devastating development in the ongoing biodiversity crisis. Authorities in Australia have warned that a catastrophic “mass bleaching event” is unfolding on the country’s famed Great Barrier Reef.

Great Barrier Reef fading

Bleaching – a process where corals expel algae living within their tissues – occurs when ocean temperatures are too high over a prolonged period. Specifically, this happens when underwater temperatures are more than 1°c warmer than the long-term average. As a result, this turns the once-vibrant corals a shade of sickly white.

While the bleached corals aren’t dead, the process puts stress on these vital organisms and leaves them vulnerable. Rapidly warming seas therefore threaten Australia’s spectacular reef system, home to thousands of marine species.

Often dubbed the world’s largest living structure, the Great Barrier Reef is a 2,300 kilometre (1,400 mile) expanse of tropical corals that house a stunning array of biodiversity.

However, repeated mass bleaching events – exacerbated by the climate crisis – have threatened to rob the tourist drawcard of its wonder.

In a statement, environment minister Tanya Plibersek said:

We know the biggest threat to coral reefs worldwide is climate change. The Great Barrier Reef is no exception. We need to act on climate change. We need to protect our special places and the plants and animals that call them home.

The damaging mass bleaching event is the seventh since 1998. Australia’s Great Barrier Reef previously suffered mass coral bleaching in 1998, 2002, 2016, 2017, 2020 and 2022. Now, following aerial surveys of 300 shallow reefs, government scientists have confirmed the latest catastrophic event is underway.

The Australian Reef Authority said it would need to conduct further surveys to assess the severity and extent of bleaching.

Climate crisis heating up the stakes

The news comes as global average sea surface temperatures set new, alarming records. The European Union’s climate modelling service Copernicus recorded the highest global sea surface temperature of 21.06°c this February. It topped the previous record high in August 2023 of 20.98°c.

According to official monitoring, ocean temperatures along the Great Barrier Reef have also approached record levels in the past few weeks.

Head of oceans at World Wildlife Fund (WWF) Australia Richard Leck said it was likely that masses of coral would die if ocean temperatures did not cool rapidly in the coming weeks. Leck said:

This bleaching event is unfolding in an area where corals have not been previously exposed to these extreme temperatures

Moreover, he emphasised that the climate crisis was “putting tremendous pressure” on the Great Barrier Reef.

On top of this, Leck added that the current bleaching event followed similar setbacks in the Northern Hemisphere in 2023. In these cases, mass bleaching caused major coral mortality in other key reef biodiversity hotspots of Florida and the Caribbean.

Rich nations are the culprit

Despite this, there is some cause for hope. Some species of bleached coral have proven remarkably resilient and can recover if ocean temperatures cool. Despite this, professor Terry Hughes, one of Australia’s foremost coral reef scientists, said bleaching events were now happening so frequently that reefs were struggling to recover.

He told AFP that:

The reef is no longer capable of recovering to the mix of coral species and the sizes of corals that were there 20 years ago. The irony is that the corals that are now prevalent on most parts of the Great Barrier Reef are fast growing and rapidly regain cover, but the kicker is that they are heat sensitive and are less tolerant to the next inevitable bleaching event.

Hughes said the heat stress had increased in the past few days and would likely worsen in the coming two weeks.

As the Canary previously detailed, the fossil-fuel-driven climate crisis is largely to blame for the increasing frequency of marine heatwaves. At 1.5°c of warming, scientists have projected that over 90% coral reefs could die.

Naturally, this makes efforts to curtail greenhouse gas emissions ever more urgent. However, governments across the world are failing to take anything like the necessary action on climate. Instead, rich nations have been doubling down on climate-wrecking expansion of fossil fuels.

Great Barrier Reef: hiding the truth

The fate of the reef has been a recurrent source of tension between the Australian government and the United Nations’ World Heritage Committee.

Specifically, the World Heritage Committee has threatened to put the reef on a list of “in danger” global heritage sites. However, Australia has fought the move that would likely damage its allure for international tourists.

In 2016, the Australian government lobbied the United Nations Educational, Scientific and Cultural Organization (UNESCO) to remove the Great Barrier Reef from a key climate report on World Heritage sites.

Then, in 2021, it once again intervened with another crucial UNESCO report. This time, it blocked a recommendation in the report calling for countries to limit global heating to 1.5°c. In particular, the original report argued for this to protect World Heritage sites from the worst impacts of the climate crisis.

Of course, like other rich nations, Australia has also been routinely bulldozing efforts to phase-out fossil fuels. On top of this, the country sits among the worst polluters.

In other words, Australia’s game plan is to hide that its natural wonder is dying, rather than tackle the underlying cause. This latest mass bleaching event shows that the stakes for this beguiling biodiverse ecosystem soar ever higher, as temperatures continue to rise. The Great Barrier Reef could soon become one of rampant extractive capitalism’s tragic ecological casualties.

Additional reporting by Agence France-Presse.

Feature image via Acropora/Wikimedia, cropped and resized to 1200 by 900, licensed under CC BY 3.0



Source link